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The Brewing Process
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Step One: Water
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Step Two: The Mash (or
that sticky porridge stuff) We take hot water from HLT 1, and mix it with malted barley (which we call Grist) and let both ingredients fall into the Mash Tun. The water temperature at this point is critical, as too low or too high and nothing much will happen. At temperatures between 61 & 70 centigrade the starch in the malted barley is converted into sugars, some fermentable, some not. The higher the temperature in the range, the higher the proportion of unfermentable sugar. This process goes on for 75 minutes, although the few minutes are the most 'active'. Getting the desired temperature comes from a balance of water, sorry liquor, temperature, against the temperature of the dry barley, and the expected heat loss through mixing the two together. A blend of malt types will help determine the colour of the beer, and part of its flavour. It we get anything wrong at this stage, it could have fatal consequences for the finished product. Once the 75 minutes is up, we start to run the beer out of the Mash Tun. This is done by draining the wort into the Underback, from where it is pumped into the Copper. A set of filet plates hold back the grist. As we do this, we spray additional hot liquor (at a slightly higher temperature) from HLT 2 over the top of grist (which now being wet, is more correctly called 'The Goods'. I told you we had to be different. Well, OK then, Odd.). Oh, and the liquor is now called Wort. Once all the wort has been run off, we are left with a lot of sticky, hot, moist stuff which we call spent 'Spent Grains'. This has to be dug out, and goes off in our case to be spread onto the fields. Traditionally this makes a good animal feed, but modern regulations have put a lot of red tape in the way of it being used as such. No doubt the Gubbinsment feels it is all a good thing. Ho hum... |
 Draining the wort into the underback |
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Step Two a: Bacon Rolls Whilst the above is going on, the hard working brewery elves have time for a bacon roll & nice hot cup of tea. Or coffee. And of course listen to the latest woes of the public as retold by Sir Terence Woebegone. |
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Step Three: On The Boil
(or towards the bitter end) The Copper is a large (well, no larger than the others) vessel, that we use to boil the wort in. It is not made of copper, but once upon a time they were, and the name seems to have stuck. Kettle is a more modern name, but as Morphy Richards didn't make ours, we'll stick with copper thank you. As the wort fills up, we begin to heat it up to boiling point. The boil normally starts about 30 minutes or so after the vessel is full, and once a good aggressive boil is acheived, we add the first charge of hops. This first hopping can be anything up to 100% of the total hops to be added, and varies with each recipe. It is from this first hopping that the traditional bitter flavours are gained, but other properties from the hops are also extracted. Mostly of a preservative nature, and in some cases (ie with our beer 'Silence') a bit of noticeable colour as well. An hour is allowed to pass, during which time all sorts of complex scientific things happen with protein molecules, plus the wort is sterilised, before we add a second charge of hops. This second charge provides a mix of aroma and additional hop flavours, ranging from spiciness through to fruitiness. Once the second hops have mixed into the beer, usually a minute or two, the heat is turned off, and the wort is allowed to rest for 25 minutes or so. During this time much of the protein in the beer collects in lumps big enough to filter out. Protein is a bad thing, and can turn a beer irretrievably hazy (unless you add chemicals that is...). |
 Inside the copper after draining. |
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Step 4: The Chill Out
Zone After the wort has rested, the beer is pumped out via a filter plate in the base of the copper that holds all the solids (ie hops etc) back, and is then passed through a second, finer, filter to remove any list bits of debris (mostly small hop leaves & hop seeds) before going through a heat exchanger. The heat exchanger (more accurately a 'Paraflow') cools the beer down to 17.5 centigrade. We do this by balancing a flow of cold liquor through the heat exchanger (via a separate route!). This cold liquor comes from the Cold Liquor Tank (CLT), and in the process becomes hot liquor, and passes to the HLT's for use in the next brew/cask washing/whatever. The cooled wort then travels through a bit of pipework to the Fermenting Vessel (FV). |
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Step 5: Pitching In As the FV fills up, we add the yeast. We use a wet yeast, ie one that we harvest from one batch (or Gyle) of beer for use in the next. Our yeast has come to us courtesy of Elgoods brewery, and there is faint family resemblance in our respective beers. Fermentation is what transforms the wort into beer, and the yeast needs a highly sterile environment to work at it's best - any outside infection will wreak havoc with the beer. This is why everything has to be clean, and why our brewery elves spend almost as much time cleaning - be it pipes, vessels or casks - as they do brewing. The yeast takes approx 3-4 days to convert the sugars to alcohol, after which a 24-36 hour rest period is allowed before we chill the beer down again. The yeast will take the wort from 17.5 centigrade to 22 centigrade (it would go higher, but we won't let it). By chilling the beer down again to around 7 centigrade, we force the yeast to become dormant, and the weaker yeast cells will drop out of suspension to the floor of the FV. Chilling also helps the beer to be more resistant to lower temperatures during it's life. |
 Filling the FV  The yeast head near the end of fermentation |
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Step 6: Racking Off After 48 hours of being chilled, the beer is transferred to the Racking Tank (RT). This is a simple vessel, which unlike the FV's, stand high above the floor allowing us to gravity fill the casks (it's easier that way see). Each cask has to be thoroughly cleaned and then sterilised before it can be filled - even a tiny bit of dirt can ruin the beer. After filling, the casks are moved into our temperature controlled store (held at approx 8 centigrade), from where they are despatched to our customers. |
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The End! And that is it. Most of the above is as it would have been done centuries ago, but today we have the ability to control and read temperatures, cool the wort/beer done quickly, and the benefit of science to understand why - and how - it all happens. Curiously, the role of yeast has only been really understood within the last 200 years or so - originally, the beer would have been allowed to start fermenting all by itself. And indeed some Belgian beers are still brewed this way, often to very good effect, as any true connoisseur of Gueuze will tell you. The modern beer factories of the bigger brewers, sorry beer makers, still have to follow much of the above, but they will take shortcuts with the aid of chemicals & enzymes, and fermentation times are greatly sped up. All to save money, and not, as they might tell you, to improve the beer's relationship with your taste buds. Assuming you still have taste buds that is... |
